The Brazil defender will start on the bench at Stamford Bridge after recovering from knee surgery.
Long time coming: Alex (centre) was a regular at the start of the season
His return gives manager Carlo Ancelotti a full squad to choose from, with David Luiz also available after being cup-tied in Wednesday night's Champions League defeat to Manchester United.
Provisional squad: Cech, Bosingwa, Ferreira, Terry, Luiz, Ivanovic, Alex, Zhirkov, Cole, Mikel, Essien, Lampard, Ramires, Benayoun, Kalou, Malouda, Anelka, Torres, Drogba, Turnbull.
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